Drilling-bit



- T. C. BUDDINGTON.

DRILLING BIT.

APPLICATION FILED MAY 22. I9I9.

Patented July 27, 1920.

2 m w w F 0 m h 5 1 M/ A..4/// AJA- E & h z ww H I ILIII o G I I I h m n w W s A 70 II I m, A AI I I 3 I Z 0; I 8 N H Y I MU HH m T B II; 5 /rb\\ 3 O XI w i a 9 O0 59 7 I 1 1 1 1 C F k Q I I u 9 I I o u 7 v m I w I I IIII., I I IIIIEHHIIII I v N l? I I I I I I I E .1 I 5 a T1 5 A 9 a I X UNITED STATES PATENT OFFICE.

THOMAS C. BUDDINGTON, OF PASADENA, CALIFORNIA, ASSIGNOR OF ONE-HALF T0 SAMUEL G. ELAM, OF PASADENA, CALIFORNIA.

DRILLING-BIT.

To all whom it may concern Be it known that I, THOMAS C. BUDDING- TON, a citizen of the United States, residing at Pasadena, in the county of Los Angeles and State of California, have invented new and useful Improvements in Drilling-Bits, of which the following is a specification. v I

This invention relates to drilling bits for oil and other wells, and it has for its object to provide an improved bit, particularly adapted for the drilling of deep wells in which casing is sunk or lowered in the hole as the drilling proceeds, the invention having for a particular object the provision of a drilling bit which will enable the drilling operation to be carried on, and the casing to be lowered, without the use of devices known as underreamers, for cutting away or drilling away or boring away the earth formation beneath thecasing. Ordinarily this shoulder or annular formation has to be removed, intermittently, by the substi and the cutters of which, while contracted when lowering the bit through the casing,

automatically expand after escaping at the.

lower end of the casing, and occupy .a

spread-out position causing them to drill or bore out the earth formation to a diameter of hole sufficiently great .to permit the casing to be lowered or to follow the bit without any underreaming operation.

All the loss of time incident to substituting underreamer for bit, and bit for underreamer, in ordinary standard dr lling practice, which involves the intermittent withdrawal of the whole string of drilling tools from the well, is thus obviated in the use of the present invention, and also the expense incident to purchase or rental, and to maintenance and repair, of underreamers is avoided.

The invention has for further objects the provision of an improved drilling bit which will be superior in point of relative simplicity and inexpensiveness of construction, taken in conjunction with convenience in use, durability, positiveness in action, and

Specification of Iietters Patent. Patented J l 27 1920 7 Application filed May 22, 1919.

Serial 1l'0.- 298,978.

reliability, and which will be generally superior in efficiency and serviceability.

With the above and other objects in view,

the invention consists in the novel and use- Fig. 2 is a view similar to Fig. 1 showing the cutters of the bit in expandedtposition, or positions of expansion, which positions are assumed after the cutters have passed beneath the bottom-of the well casing, such cutters being shown in contracted position or condition of contraction, in Fig. 1; and v Fig. 3 is a detail transverse sectional view, taken upon the line :12 -m Fig. 1, and looking in the direction of the appended arrows. Corresponding parts'in all the figures are designated by the same reference characters.

Referring with particularity to the drawing, A designates the stem of the improved bit,'provided at its upper end with a shackle a pivoted to the stem as at 4, and by which shackle the bit is connected with thesdrilling rope or cable or other drilling tools, if required or desired, such as jars. At the lower end of the stemA is providedthe bit stock I), which is preferably rectangularin cross section, and provided at each of its four faces with a separate cutter B, such cutters being mounted in connection with the stock b of the bit, so that the cutters have a tendency to swing outwardly at their lower ends, from the positions indicated in Fig. 1, to

the positions in Fig. 2, when such cutters separate flat face 7 of the bit stock I), being so pivotally connected through the agency of two bolts 8, which are passed-transyersely through the bit stock I), at right angles to each other, and one above the other, projecting sufiiciently beyond opposed faces 7 of,

tendency to swing out at their lower sharpened cuttlng edges 10, in a series extending 7 around the stock I) uniformly, so that in pro ceeding around the stock in one direction a corresponding direction of projection of the expanded cutters exists. Thus, when the cutters are in expanded positions as shown in Fig. 2, they comprise a Working group of uniformly expanded cutters, their expansion being limited by stop means E which preferably consist of stop pins 11 disposed adjacent to the top portion of the stock b, one, foreach face 7 of such bit stock, and'slightly disposed atone side of a vertical plane pass ing through the pivotal center of the corresponding cutter'body, being sodisposed at that side of such plane as corresponds with the location of the narrower side of the pivotally suspended cutter body.f In other words, each stop pin is disposed slightly more eccentrically with respect to the corresponding cutter, that is, to its point of pivotal'su'pport. Asclearly shown in Fig. 2,

each cutter swings up against its stop pin 11,

at the upper edgeofthe cutter, when such cutter is in'expanded or projected position at itslower'edge, and the up-thrust 'of the cutter, resultingfrom its engagement with the earthformation, in reciprocation of the cutter in drilling, is imparted to the bit stock through there spective bolt Sand stop pin 11. The cutters automatically expand when liberated from the confining or restraining casing, and assume. positions shown in Fig. 2, in which positions they act tochip or cut away the formation and de velop well hole, upon their reciprocation which is produced by the walking beam at the surface of the well, in the ordinary manner.

I have shown a circulation system for the bit, the softening action of the liquid supplied by which assists the bit in the cutting operation, and produces a mud'or detritus in:

suspension which is bailed out of the hole or otherwise withdrawn. This circulation systern includes a casing F applied to the bit stem .A, so as to provide a chamber f surrounding the bit stem, the casing to that end vsponding cutter andso as to discharge its fluid downwardly into the zone of the cut having a central tubular portion 12 which receives and accommodates the bit stem A, such casing F being held in position of adjustment in connection'with the stem by one or more set screws 13 applied to the bit stem through an upward projection 13 upon the top of the tubular portion 12. Acircular pipe 14 enters the upper portion of the closed casing F, and supplies the casing with liquid, whereas discharge pipes 15 range downwardly from the lower portion of the casing, in a series of four, one for each cutter B, and each such discharge pipe being disposed slightly outwardly of the correting operation of the cutter.

It is believed that no further statement of the operation of the invention, or of its advantages, will be-required, in addition to that above given, inasmuch as it will be obvious that the expanded cutters will chip and cut and break away the formation, upon reciprocation of the bit in the drilling operation, the cutters automatically expanding to their working positions after they have passed beneath the lower end of the casing, and automatically enter the casing, or collapse, upon the elevation of the drilling 7 string. The cutters will effectively reduce the earth formationto produce a hole hav ing a diameter slightly greater than the outer diameter of the casing and its shoe, or sufficiently large to permit the casing to be lowered or driven down without the use of anyunderreamer or underreaming operation, thus saving a large amount of time and expense, in interchange of 'bit for under reamer and underreamer for bit, and in cost of underreaming tools and the expense of'105.

maintenance thereof. All of this makes for speedy and effective drilling action, and

I the cutter and bit in actual practice is found to make hole rapidly andeffectively, par

ticularly in shale and other softerformations. It is to be'further noted that the casing F is 'adjustably connected with the bit stem A, so that its position may be shifted to vary the height above the lower ends of the cutters B, at which height the liquid is to be discharged or released from the discharge pipe 15, all in accordance with preference or requirements of service. 7 It is obvious that many changes and varia- 1 tions may be made, with respect to the foregoing description and the showing of the drawing, in practising the invention, and in adapting the invention to varying conditions ofuse and service, without departing from the true spirit of the invention.

Having thus disclosed 'm invention, I claim and desire to secure by {letters Patent 1. A bit, comprising a bit stock provided with a cutter eccentrically suspendedfrom the bitstock and thus having an inherent 130 I mounted.

2. A bit, comprising a bit stock provided with a cutter eccentrically suspended from the bit stock and thus having an inherent tendency to project laterally into drilling position; in combination with liquid circulation means comprising a casing, means for connecting the casing with the bit stock, and a liquid supply pipe extending to the casing; said bit stock being provided with a stem upon which said casing is mounted above the bit stock.

3. A drilling bit, comprising a bit stock, and a plurality of eccentrically pivoted cutters mounted in connection with said bit stock and having an inherent tendency toward lateral projection at their cutting p0r-- tions; bolts being provided through said bit stock and projecting beyond opposite faces thereof, said cutters being, mounted upon said projecting bolt ends, means being provided exteriorly of the cutters to prevent displacement thereof from the bolt ends.

In testimony whereof, I have signed my name to this specification in the presence of two subscribing Witnesses.

THOMAS C. BUDDINGTON.

WVitnesses:

RAYMOND IvEs BLAKESLEE, MILDRED LEACH. 

